JP5009745B2 - Ultrasonic diagnostic equipment - Google Patents

Description

  The present invention relates to an ultrasonic diagnostic apparatus, and more particularly to an ultrasonic diagnostic apparatus that sets a region of interest surrounding a diagnosis target.

  The ultrasound diagnostic device collects a plurality of echo data from the space including the in-vivo tissue and the diagnosis target such as fetus and tumor, and based on the plurality of echo data, an ultrasonic image such as a tomographic image or a three-dimensional image Can be formed. In general, an ultrasonic image includes an image of a part other than a diagnosis target. Therefore, for example, a region of interest (ROI) surrounding the diagnosis target is set in the ultrasonic image for the purpose of improving the accuracy of the process of extracting only the diagnosis target. Conventionally, various techniques relating to setting of a region of interest have been proposed.

  For example, Patent Document 1 describes a technique for setting the position of a region of interest of a plurality of frames between two frames by interpolation calculation. Patent Document 2 describes a technique for setting a region of interest using a region expansion method. Japanese Patent Application Laid-Open No. 2004-228561 describes a technique for arranging a region of interest at an optimal position. Patent Document 4 describes a technique for correcting a region of interest using a non-linear margin segment set by a user.

JP 2005-328948 A JP 2000-172829 A JP 2003-325511 A JP 2006-61698 A

  As described above, while various techniques related to the setting of the region of interest have been proposed, the inventor of the present application has repeatedly researched and developed an improved technique related to the setting of the region of interest. In particular, we paid attention to technologies for easily setting a region of interest, technologies for setting a region of interest that appropriately surrounds a diagnosis target, and technologies that can be applied not only to two dimensions but also to three-dimensional regions of interest.

  The present invention has been made in the course of research and development, and an object thereof is to provide an improved technique relating to the setting of a region of interest.

  In order to achieve the above object, an ultrasonic diagnostic apparatus according to a preferred aspect of the present invention includes a probe that transmits and receives ultrasonic waves in an area including a diagnosis target, and a plurality of echoes from within the area by controlling the probe. A transmission / reception unit that obtains data, a region of interest setting unit that sets a region of interest surrounding a diagnosis target with respect to an ultrasonic image formed from a plurality of echo data, and an image display unit that displays an ultrasonic image The region-of-interest setting unit adds a setting process for setting a temporary region of interest in an ultrasound image, a specifying process for specifying a boundary portion of the temporary region of interest where the diagnosis target protrudes, and a size of the boundary portion A determination process for determining a region and a correction process for correcting the provisional region of interest by adding an additional region to the boundary portion are executed, and the corrected provisional region of interest is used as the region of interest.

  According to the above aspect, since the temporary region of interest is corrected at the boundary portion where the diagnosis target protrudes, the region of interest that appropriately surrounds the diagnosis target can be set as compared with the case where the correction is not performed. Further, since the additional region is determined according to the size of the boundary portion, the provisional region of interest can be easily corrected as compared with the case where the user manually determines the additional region. Moreover, the said aspect is applicable not only to two dimensions but to a three-dimensional region of interest.

  In a preferred aspect, the region-of-interest setting unit performs the specific process, the determination process, and the correction process on the corrected provisional region of interest as a processing target, thereby repeatedly correcting the temporary region of interest to the region of interest. It is characterized by.

  In a preferred aspect, the region-of-interest setting unit sets a three-dimensional provisional region of interest in the three-dimensional ultrasound image in the setting process, and identifies a boundary portion of the three-dimensional provisional region of interest in which the diagnosis target protrudes in the specifying process Determining a spherical additional area having a radius corresponding to the size of the boundary part in the determination process, and adding a spherical additional area to the boundary part in the correction process to correct the three-dimensional provisional region of interest, The modified three-dimensional temporary region of interest is used as the region of interest.

  In a preferred aspect, the region-of-interest setting unit sets a two-dimensional provisional region of interest in the two-dimensional ultrasound image in the setting process, and identifies a boundary portion of the two-dimensional provisional region of interest in which the diagnosis target protrudes in the specifying process In the determination process, a circular additional area having a radius corresponding to the size of the boundary part is determined, and in the correction process, a circular additional area is added to the boundary part to correct the two-dimensional provisional region of interest, The modified two-dimensional temporary region of interest is used as the region of interest.

  The present invention provides an improved technique for setting a region of interest. For example, in the preferred embodiment of the present invention, since the temporary region of interest is corrected at the boundary portion where the diagnosis object protrudes, the region of interest that appropriately surrounds the diagnosis object can be set as compared with the case where the correction is not performed. In the preferred embodiment of the present invention, since the additional region is determined according to the size of the boundary portion, the temporary region of interest can be easily corrected as compared with the case where the user manually determines the additional region. .

  Hereinafter, preferred embodiments of the present invention will be described. FIG. 1 shows a preferred embodiment of an ultrasonic diagnostic apparatus according to the present invention, and FIG. 1 is a functional block diagram showing the overall configuration thereof.

  The probe 10 is an ultrasonic probe that transmits and receives an ultrasonic wave in a region including an object to be diagnosed. The target object in the present embodiment is, for example, tissue in the living body, blood flow, fetus, tumor, or the like. The probe 10 includes a plurality of vibration elements. The plurality of vibration elements are arranged in one row and electronically controlled, for example, so as to transmit and receive ultrasonic waves two-dimensionally within the region. Note that ultrasonic waves may be transmitted and received three-dimensionally by arranging a plurality of vibration elements two-dimensionally in a lattice shape and electronically controlling.

  The transmission / reception unit 12 outputs a transmission signal corresponding to each of the plurality of vibration elements included in the probe 10. The transmission / reception unit 12 applies a delay process or the like corresponding to the vibration element to the transmission signal of each vibration element. The transmission signal output from the transmission / reception unit 12 is supplied to each vibration element of the probe 10. That is, the transmission / reception unit 12 functions as a transmission beamformer, each vibration element vibrates in accordance with a transmission signal formed by the transmission / reception unit 12, an ultrasonic transmission beam is formed, and scanning of the transmission beam is controlled.

  In addition, the transmission / reception unit 12 forms a reception beam based on reception signals obtained from a plurality of vibration elements included in the probe 10. The transmission / reception unit 12 performs a delay process or the like according to the vibration element on the reception signal of each vibration element, and adds the reception signals obtained from the plurality of vibration elements. That is, the transmission / reception unit 12 functions as a reception beam former, and forms reception beam data by performing, for example, phasing addition processing on reception signals output from a plurality of vibration elements. In this way, reception beam data (echo data) is collected from the entire area in the two-dimensional or three-dimensional area.

  The ultrasonic image forming unit 14 forms image data of an ultrasonic image based on the reception beam data formed in the transmission / reception unit 12. For example, image data of a two-dimensional B-mode image is formed based on reception beam data obtained by two-dimensionally scanning an ultrasonic transmission beam. Of course, image data of a three-dimensional ultrasonic image may be formed based on received beam data obtained by three-dimensionally scanning an ultrasonic transmission beam.

  The display image processing unit 16 forms a display image based on the ultrasonic image (image data) formed in the ultrasonic image forming unit 14. Further, the display image processing unit 16 forms a display image, a user interface image, and the like corresponding to the apparatus state of the ultrasonic diagnostic apparatus. The display image formed in the display image processing unit 16 is displayed on the display unit 18.

  The operation device 22 is a device that receives a user operation. The operation device 22 is, for example, a trackball, a mouse, a keyboard, a touch panel, or the like, and is provided in the apparatus main body of the ultrasonic diagnostic apparatus. The control unit 20 controls each unit in the ultrasonic diagnostic apparatus. For example, the control unit 20 controls each unit in the apparatus in accordance with a user operation input via the operation device 22.

  In the present embodiment, the region of interest surrounding the object is set in the ultrasonic image (image data) formed by the ultrasonic image forming unit 14 by the region of interest setting unit 24. Therefore, the region-of-interest setting process in the present embodiment will be described below. 1 is used in the following description for the portion (configuration) already shown in FIG.

  FIG. 2 is a flowchart for explaining region-of-interest setting processing in the present embodiment. When an ultrasound image (image data) is formed by the ultrasound image forming unit 14 (S201), the region-of-interest setting unit 24 temporarily provisions a region of interest that surrounds the object with respect to the formed ultrasound image. Is set as a provisional region of interest (S202).

  The provisional region of interest is set, for example, when the user (inspector) operates the operation device 22 while viewing the ultrasonic image displayed on the display unit 18. When the ultrasonic image is a two-dimensional image, the size and position of an ellipse, for example, is designated by the user in the displayed two-dimensional image, and an elliptical provisional region of interest is set. Further, when the ultrasonic image is a three-dimensional image, for example, three cross sections of the front surface, the side surface, and the upper surface relating to the three-dimensional image are displayed on the display unit 18, and an ellipsoid or the like is used by using each displayed cross section. The size and position are designated by the user, and for example, an elliptical provisional region of interest is set.

  Note that an elliptical or elliptical provisional region of interest may be automatically set in the ultrasound image. For example, an ellipse or ellipsoid centered on the center position of the ultrasonic image may be automatically set as the temporary region of interest. Further, the provisional region of interest may be an ellipse or a shape other than an ellipsoid.

  When the provisional region of interest is set, the boundary of the object is extracted in the ultrasonic image (image data) (S203). For example, each pixel data in the ultrasonic image is binarized by a threshold value for distinguishing the object from other parts, and a plurality of pixel data corresponding to the object are extracted. Then, pixel data corresponding to the boundary is extracted from among a plurality of pixel data corresponding to the target object, for example, based on a determination criterion such as whether or not the pixel data is adjacent to another part.

  When the boundary of the object is extracted, the region-of-interest setting unit 24 checks whether the boundary of the object exceeds the provisional region of interest and exists outside the provisional region of interest (S204). For example, by comparing the coordinate information of the boundary of the object in the ultrasonic image with the coordinate information of the boundary of the provisional region of interest, it is confirmed whether the boundary of the object exists outside the provisional region of interest. .

  If the boundary of the object does not exist outside the provisional region of interest, it is determined that the object is appropriately surrounded by the provisional region of interest, and the provisional region of interest is set as a normal region of interest. Is displayed on the display unit 18 (S208). When the boundary of the object exists outside the temporary region of interest, that is, when the object protrudes from the temporary region of interest, the correction process of the temporary region of interest described below is executed.

  When the object is protruding, the region-of-interest setting unit 24 identifies the boundary portion of the temporary region of interest where the object protrudes (S205), and further, the center of the additional region according to the size of the specified boundary portion. The position and radius are determined (S206), and an additional region is added to the boundary portion where the object of the temporary region of interest protrudes to correct the temporary region of interest (S207).

  FIG. 3 is a diagram for explaining the temporary region-of-interest correction process by the region-of-interest setting unit 24. FIG. 3A is an example of an ultrasonic image (two-dimensional image) in which the temporary region of interest 32 is set so as to surround the object 40.

  The region-of-interest setting unit 24, for example, based on the coordinate information of the boundary of the target object 40 and the coordinate information of the boundary of the temporary region of interest 32 in the ultrasonic image, the boundary portion of the temporary region of interest 32 where the target object 40 protrudes. Is identified. In addition, the pixel data part of the target object 40 may be extracted as a boundary part by extracting the pixel data of the target object 40 from a plurality of pixel data corresponding to the boundary of the provisional region of interest 32.

  When the boundary portion is specified, an additional region 34 is added to the specified boundary portion as shown in FIG. FIG. 3B shows a state in which the additional region 34 is added to each of the two boundary portions where the object 40 protrudes. The region-of-interest setting unit 24 determines the center position and radius of the additional region 34 according to the size of the boundary portion.

  FIG. 3B ′ is an enlarged view of one of the additional areas 34 shown in FIG. The region-of-interest setting unit 24 sets a line segment connecting both ends of the boundary portion of the provisional region of interest 32 where the object 40 protrudes, that is, the portion of the one-dot chain line portion shown in FIG. Set the center coordinate O to. Further, a circular additional region 34 having a center coordinate O having a radius of the distance A from the center coordinate O to the end point of the line segment or a distance (A + α) provided with a margin in the distance A is set. For the other of the additional regions 34 shown in FIG. 3B, the center coordinates and radius of the additional region 34 are determined based on the size of the boundary portion where the object 40 protrudes.

  When the additional region 34 corresponding to each boundary portion is determined in this way, the corresponding additional region 34 is added to each boundary portion to form a provisional region of interest 30 that is modified as shown in FIG. Is done. The region-of-interest setting unit 24 is included in at least one of the region obtained as a logical sum (OR) of the temporary region of interest 32 and the additional region 34 before correction, that is, the temporary region of interest 32 and the additional region 34 before correction. A region composed of a plurality of pixel data is set as a corrected provisional region of interest 30.

  When the ultrasonic image is a three-dimensional image, front, side, and upper surface sectional images obtained from the three-dimensional image are obtained, for example, as shown in FIG. Then, for each cross-sectional image, the boundary portion where the object 40 protrudes is extracted, and the center coordinate O and the distance A are determined for each boundary portion in each cross-sectional image, as shown in FIG. Calculated.

  Further, the center coordinate O in the three-dimensional coordinate system is determined based on the center coordinate O obtained from each of the three cross-sectional images of the front surface, the side surface, and the upper surface for the same boundary portion in the three-dimensional image. Further, for the same boundary portion in the three-dimensional image, among the distances A obtained from each of the three cross-sectional images, for example, the maximum distance A is selected, and a sphere having a radius of the distance A (or A + α) is formed. Then, the center of the sphere is set to the position of the center coordinate O in the three-dimensional coordinate system.

  Thus, when the ultrasonic image is a three-dimensional image, for example, a spherical additional region 34 is added to the ellipsoidal temporary region of interest 32 to form a corrected three-dimensional temporary region of interest 30.

  Returning to FIG. 2, when the additional region is added to the boundary portion and the provisional region of interest is corrected (S207), the boundary of the object is extracted again (S203), and the boundary of the object is corrected. It is confirmed whether or not the temporary region of interest exists outside the temporary region of interest (S204).

  If the boundary of the object does not exist outside the modified provisional region of interest, it is determined that the object is appropriately surrounded by the modified provisional region of interest, and the provisional region of interest is set as the regular region of interest. The When the boundary of the target exists outside the corrected provisional region of interest, that is, when the target is protruding, the processing from S205 to S207 is further executed, and further to the corrected provisional region of interest, Modifications are made. As described above, when the object protrudes from the corrected provisional region of interest, the processing from S205 to S207 is repeated, and the provisional region of interest is repeatedly corrected. A limit may be set for the number of times of repeated correction.

  FIG. 4 is a diagram illustrating a state in which correction is repeatedly performed on the temporary region of interest. For example, as shown in FIG. 4, when a part of the object 40 protrudes long, a part of the object 40 may protrude from the initially set elliptical or ellipsoidal temporary region of interest 32. Conceivable. In the case shown in FIG. 4, a plurality of additional regions 34 are added stepwise along the protruding direction of the target object 40 by repeatedly correcting the temporary region of interest. For example, the next additional region 34 is added to the additional region 34 added by the previous correction process, and the plurality of additional regions 34 are connected one after another, so that the region of interest is corrected so as to surround the object 40. .

  As described above, according to the present embodiment, the region of interest is appropriately corrected even for the object 40 having a special shape as shown in FIG. Of course, even in a case other than the shape shown in FIG. 4, the additional region 34 is repeatedly added as necessary, and the region of interest is appropriately corrected.

  As described above, the preferred embodiment of the present invention has been described. However, according to the above-described embodiment, the temporary region of interest is corrected at the boundary portion where the object protrudes. A region of interest can be set. Further, since the additional region is determined according to the size of the boundary portion, the provisional region of interest can be easily corrected as compared with the case where the user manually determines the additional region. Note that by automatically setting the first provisional region of interest, it is possible to perform the processing from the setting of the first provisional region of interest to the setting of the regular region of interest fully automatically.

  As mentioned above, although preferred embodiment of this invention was described, embodiment mentioned above, its effect, etc. are only a mere illustration in all points, and do not limit the scope of the present invention. The present invention includes various modifications without departing from the essence thereof.

1 is a functional block diagram showing an overall configuration of an ultrasonic diagnostic apparatus according to the present invention. It is a flowchart for demonstrating the setting process of a region of interest. It is a figure for demonstrating the correction process of a temporary region of interest. It is a figure which shows a mode that correction is repeatedly performed with respect to a temporary region of interest.

Explanation of symbols

  10 probe, 12 transmitting / receiving unit, 14 ultrasonic image forming unit, 24 region of interest setting unit.

Claims (4)

A probe for transmitting and receiving ultrasonic waves in a region including a diagnosis target; and
A transmission / reception unit for obtaining a plurality of echo data from within the region by controlling a probe;
A region-of-interest setting unit that sets a region of interest that surrounds a diagnostic target for an ultrasound image formed from a plurality of echo data;
An image display unit for displaying an ultrasonic image;
Have
The region of interest setting unit
A setting process for setting a provisional region of interest in the ultrasound image;
A specific process for identifying the boundary portion of the provisional region of interest that protrudes from the diagnosis target;
A determination process for determining an additional area according to the size of the boundary part;
Correction processing for correcting the provisional region of interest by adding an additional region to the boundary part,
Run
The modified provisional region of interest is the region of interest,
An ultrasonic diagnostic apparatus. The ultrasonic diagnostic apparatus according to claim 1,
The region-of-interest setting unit sets the corrected provisional region of interest as the region of interest repeatedly by executing the specifying process, the determination process, and the correction process with the corrected provisional region of interest as a processing target.
An ultrasonic diagnostic apparatus. The ultrasonic diagnostic apparatus according to claim 2,
The region of interest setting unit
In the setting process, a 3D provisional region of interest is set in the 3D ultrasound image,
Identifying the boundary portion of the three-dimensional provisional region of interest where the diagnostic object protrudes in the identifying process;
In the determination process, a spherical additional area having a radius corresponding to the size of the boundary portion is determined,
By correcting the three-dimensional provisional region of interest by adding a spherical additional region to the boundary in the correction process,
The modified three-dimensional provisional region of interest is the region of interest,
An ultrasonic diagnostic apparatus. The ultrasonic diagnostic apparatus according to claim 2,
The region of interest setting unit
In the setting process, set a two-dimensional provisional region of interest in the two-dimensional ultrasound image,
Identifying the boundary portion of the two-dimensional provisional region of interest where the diagnostic object protrudes in the identifying process;
In the determination process, a circular additional area having a radius corresponding to the size of the boundary portion is determined,
By correcting the two-dimensional provisional region of interest by adding a circular additional region to the boundary part in the correction process,
A modified two-dimensional provisional region of interest as the region of interest;
An ultrasonic diagnostic apparatus.

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